This overnight tater tot casserole is packed with flavor and super easy to make. Make it the night before a holiday or early morning and wake up to a cooked breakfast that's both hearty and filling.
Cook meats. In a skillet over medium heat, brown the sausage with the onion and bell pepper, crumbling the sausage as it cooks. Transfer to a bowl. Cook the bacon until crisp, chop, and drain excess grease.
Mix filling. In a large bowl, whisk together the milk, sour cream, eggs, salt, cayenne, black pepper, and half of each shredded cheese. Stir in the cooked sausage mixture and bacon.
Assemble. Arrange the frozen tater tots in an even layer in the prepared baking dish. Pour the egg and meat mixture evenly over the top. Sprinkle with the remaining cheese.
Chill. Cover and refrigerate overnight.
Bake. Let the casserole rest at room temperature while the oven preheats to 350°F. Bake covered with foil for 30 minutes, then uncover and bake for another 30 minutes, until set and heated through.
Finish. Sprinkle with green onions if using. Let rest 10 minutes before slicing. Serve with salsa if desired.
Notes
Baking tips. Internal temperature should reach 165°F. If tots were very frozen, additional bake time may be needed.
Shortcut option. For same-day prep, thaw tots on a baking sheet while preparing the filling or bake tots per package directions, cool, then assemble.
Potato swaps. Tater tot coins, hashbrown sticks, or similar frozen potatoes work well.
Storage. Store leftovers covered in the refrigerator for 3–4 days and reheat before serving.